Mussels

When you want to spend a relaxing day outdoors in the Heartland, few places are more peaceful than Rockford Beach Park, just northwest of House Springs in east central Missouri. A low head dam, built in the late 1890s to power the now nonexistent Rockford/Bonacker Mill, still stretches partway across the Big River. This aging dam creates a tranquil waterfall that has enticed patrons of the Jefferson County Parks system for decades.

Photo of old Rockford/Bonacker Mill, near present location of Rockford Beach Park. (Courtesy of Jefferson County, Mo. Library, Northwest Branch, Special Collections)

Other patrons of the Big River also enjoy the benefits provided by the Rockford Beach dam: a vast, diverse community of freshwater mussels. Yet, unbeknownst to many, just below the babbling waters of the Big River, these abundant mussel species are becoming more endangered every day.

A visual inspection of the dam conducted by the Missouri Department of Natural Resources (MDNR) in January 2015 found that it had experienced heavy deterioration and was in a state of partial failure. Sections of the stone had washed away, leaving voids beneath the surficial concrete shell. Moreover, MDNR noted that if no action was taken, the dam would eventually experience a total breach.

EPA was placed in charge of this project because if the dam were to fail completely, it would result in the release of stored sediment behind the dam, which is contaminated with mining-related metals, and just 200 yards downstream from the Rockford Beach dam are three federally-listed, endangered mussel beds.

Eastern portion of Rockford Beach dam

I’m a remedial project manager in the Special Emphasis branch of the Superfund program at EPA Region 7, and was assigned to the Rockford Beach dam project in September 2015. I had been working with the U.S. Army Corps of Engineers (USACE) on several other projects through interagency agreements, so I was familiar with the process and had pre-established contacts within the USACE in the St. Louis area.

A 2009 study of freshwater mussels throughout the Big River found a total of 2,198 living specimens representing 33 unionid species at 19 study reaches in the river. Nine species of state conservation concern were found, including three federally-listed species (Pink Mucket, Lampsilis abrupta; Scaleshell Mussel, Leptodea leptodon; and the recently listed Spectaclecase, Cumberlandia monodonta). The majority of the mussel population in the Big River occurs downstream from the Rockford Beach dam.

A breach or failure in the remaining section of the dam would release trace elements of lead, arsenic, barium, cadmium and zinc – all elements routinely found around older mining and industrial sites. As benthic, filter-feeding organisms, freshwater mussels are directly exposed to contaminants in sediment and surface water.

That kind of significant release would severely impact a large number of freshwater mussel species located downstream, and the Big River has an incredibly diverse mussel community.

Apart from biological impact to the endangered mussel beds, the failure of the Rockford Beach dam could present a myriad of other environmental and safety issues to the surrounding area. That contaminated sediment, if released, would be made available downstream to the floodplain and further into the Meramec River. Those deposits could disperse a concentrated volume of lead into the environment, making it a much larger problem to remediate in the future.

Construction to stabilize western portion of Rockford Beach dam

In January 2016, EPA entered into an Interagency Agreement (IAG) with USACE to conduct a removal action to stabilize the western portion of the dam. The eastern portion of the dam had already partially failed, which now allows for fish passage. This partial failure was not significant enough to cause the release of built-up contaminated sediment. Under the IAG, the USACE planned, designed, and constructed an interim solution to stabilize the western side of Rockford Beach dam.

Many other state and local agencies provided support to the project, including local fire and police departments, the U.S. Fish and Wildlife Service, Missouri Department of Conservation, and MDNR’s Dam and Reservoir Safety Program.

In Superfund, we often work on projects that can span a lifetime, so it’s nice to be able to start a project, see it run smoothly, and witness the completion. It’s not often that you get to work on a project that allows you to build strong and lasting relations with a community, and at the same time, protect and safeguard endangered species.

About the Author: Cody McLarty serves as a remedial project manager in EPA Region 7’s Superfund program. He mainly works in the southeast Missouri mining district. Cody has a bachelor’s degree in conservation biology from the University of Texas at Austin, and a master’s degree in engineering management from the University of Kansas.

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These mussels help to filter the Delaware River by removing sediment, algae and pollutants.

by Steve Donohue

During a recent survey on the Delaware River, I helped collect for scientific research, a freshwater mussel that was likely in the river below me when I was a kid in the 60s driving over a nearby bridge in the backseat of our family’s station wagon. While some species can live to 100 or more, the one I’m holding – and after examining, returned to the water – is probably 50-60 years old and has been silently filtering water all that time.

These freshwater bivalves, like their saltwater relatives, oysters, provide valuable “ecosystems services” by filtering water and removing sediment, algae, and pollutants, while also stabilizing the bottom substrate. According to the Partnership for the Delaware Estuary (PDE), a National Estuary Program partner, one adult mussel can filter 20 or more gallons of water a day so this one mussel has probably treated several hundred thousand gallons of water over its lifetime. Multiply that by hundreds or thousands of mussels in a healthy population and the numbers add up quickly.

Not long ago it was believed some species of freshwater mussels were extinct in the Delaware River due to pollution and spills from the River’s industrial past, over-harvesting for bait, loss of forests along streams, loss of fish hosts needed for reproduction, and dams that block fish passage.

In 2007, the PDE launched the Freshwater Mussel Recovery Program (FMRP) to help the comeback of the one dozen native species classified as reduced, threatened, or locally extinct.

EPA’s Scientific Dive Unit is collaborating with PDE, the Academy of Natural Sciences of Drexel University and the Philadelphia Water Department in restoration efforts. One goal is to determine where freshwater mussels are located, and how many are present. This will help quantify the current benefit they provide to water quality in the Delaware and the potential benefit a larger, healthy population would provide for future generations.

About the author: Steve Donohue has been an environmental scientist at EPA for over 25 years. He is the Unit Dive Officer on the EPA Mid-Atlantic Scientific Dive Unit and works to address climate change issues and improve the efficiency and sustainability of public and private sector facilities.

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Over the past two weeks I’ve told you about one of my favorite rivers (the Blue River) and favorite aquatic species (Mussels). Although the Blue River currently supports nearly 17 mussel species, habitat alteration, pollution, and the introduction and spread of non-native clams (Corbicula) have led to the extinction of some species from the river. More than half the surviving native mussel species at 159th exhibit declining populations. Mussels as a group are considered one of the most imperiled freshwater organisms in North America. Mussels are in serious danger and many of the declines in mussel populations at 159th and other sites on the river can be attributed to flood-control and urbanization projects.

Many of the lower reaches of the Blue River have been channelized. In fact, when we arrived last summer (2012) to sample the Byram’s Ford site, we found the river had been altered and straightened. Flood-control projects like the one at Byram’s Ford result in the loss of habitat for mussels and other aquatic life. The original habitat at this site was riffles, runs, and some backwaters with a medium bend in the river. Now, the river is deep and straightened, and it is hard to get in to sample. Riffles aerate the river and provide essential dissolved oxygen for many aquatic organisms. Bass, sunfish, madtoms, darters, and many minnow species use riffles for food, reproduction and shelter. Riffles are important for mussels as well. In 2009, this site had a productive mussel community including one SINC species, the Yellow sandshell (See the Table below).

The original riffles, gravel bars, and adjacent backwaters also were important feeding areas for waterfowl and herons. Ultimately, with the loss of riffle habitat and the increase in water depth, we may see a decline in the diversity and abundance of some mussel species at this site. The following picture of the Blue River at Coalmine Road (not far from the Stadiums) gives you an idea of what the river looks like lower in the watershed.

Since coming on board with EPA, I have observed a number of changes to the upper Blue River basin. When I was enrolled in classes in the 1970s at Johnson County Community College, Antioch Road was just two lanes and the land south of the college was mostly farmland and pastureland. Over the years, construction crews have widened many of these roads to accommodate the accelerated growth moving into south Johnson County. On my field trips to stream monitoring sites in the county, I have observed many water quality problems associated with all this new growth. I am usually disgusted by the way construction crews build silt fences and how these fences never do their intended job of preventing exposed dirt from running off into waterways. These types of activities contribute to the runoff of sediments into streams which can bury mussels. Also, mussels are very sensitive to many other types of pollution as a result of stormwater runoff from parking lots and residential lawns. Heavy metals, pesticides and herbicides are some of the constant water quality problems mussels must face in the Blue. In the future, the conservation of native mussels will depend upon how well we protect the land from soil erosion and stormwater runoff. Basically, we need to take care of our watersheds.

Over the years I have been collecting and observing freshwater mussels from streams throughout Kansas and Missouri. The Blue River at 159th (shown above during high water) is a gem of a site. At this time, I believe that the physical, chemical and biological attributes are very good at this site. Every time I have sampled this urban stream site, there is good flowing, permanent water, which most mussel species require. It will be interesting to discover in the coming years what aquatic species are able to live and tolerate the rapid environmental changes that are occurring in the Blue River basin. And, this is especially true for the mussels in the Blue at 159th.

Craig Thompson lives near the mussel-less (except for Asian clams) Brush Creek, a tributary of the Blue River. He is a Life Scientist with the Environmental Assessment and Monitoring Branch (EAMB). Craig joined EPA in 2009 after spending thirteen years with Kansas Department of Health and Environment. He assists EAMB staff with water quality and biological sampling surveys throughout the Region 7 area.

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Last week I posted a blog article discussing Mussels in the Blue River, and the work performed by the Kansas Department of Health and Environment (KDHE) and by EPA Region 7 over the last several decades to conduct qualitative mussel surveys. Last weeks blog focused mostly on rare species. This week I will be discussing the relative abundance of species in the Blue River (collection sites are shown below in the Figure 1.).

Figure 1. Mussel sample sites on the Blue River

Figure 2. Corbicula fluminea

To record mussel community information, KDHE and EPA used the following – waterbody, location, scientific name, common name, collection date, collectors, relative abundance, shell condition, and width/length measurements. I mentioned last week that there are about 45 species of mussels recorded for the state of Kansas (approximately 69 for Missouri). One of the things I enjoy while collecting mussels is to identify them by their scientific name. With only 45 species of mussels compared to hundreds of species of aquatic insects they are much easier to remember and memorize. One of the most abundant shells found at 159th is from the Asian clam (Corbicula fluminea, Figure 2). Corbicula is a small, non-native clam that was introduced years ago and has since populated most waterbodies of the United States. It has many evenly-spaced concentric ridges on its outer shell, and it has been collected at every site along the Blue. At this time, there are no Zebra mussels (Dreissena polymorpha) in the Blue.

The most common native mussel species found at 159th are the Mapleleaf, Threeridge, Giant floater, Pondmussel, and White heelsplitter (Table 1). These species also appear frequently at other sites along the river. A Mapleleaf (Quadrula quadrula, Figure 3) has a thick shell that is quadrate in shape. It has a line of pustules on the outer part of its shell. When I am sampling any site on the Blue I usually find Mapleleafs together with Threeridge mussels. Threeridge (Amblema plicata) has a thick shell with three horizontal ridges (sometimes more). Giant floater (Pyganodon grandis) is another mussel with an interesting name. If you want to have some fun with the shells, place the shells in the water with the inside part (the pearly interior) facing up and you will see them float down the river. The shell of this mussel is very thin and can break easily in younger specimens. Older specimens can get quite large and up to ten inches in length. Pondmussels (Ligumia subrostrata) are common in small streams and ponds throughout the area. The shell is elongate and smooth with growth lines. You can easily tell the sexes of this species (called sexual dimorphism). Males have a longer shell that is more pointed than females. Female Pondmussels are shorter and more inflated. White heelsplitter (Lasmigona complanata) is a large mussel associated with medium to large rivers and it’s shell is ovate and smooth and the nacre is white. This mussel may have received its common name from people stepping on it barefoot.

Table 1. Relative abundance of mussel shells recorded during 21 sampling visits from the Blue River at 159th St. & Kenneth Rd. (KDHE & EPA 1991-2011). Relative abundance recorded as present < 3; common >3 but < 8; abundant >8.

One day, and on my own time, I just decided to take a look upstream from 159th. I received permission to get on the river from a piece of property managed by the Kansas Land Trust. In September, I found five different species of mussel shells (Table 2) on a gravel bar, and I also observed several live Mapleleaf and Threeridge mussels in a shallow run. These two species are very common in streams in Kansas. Their thick shells were once used to make buttons but are now used to produce pearls for the cultured pearl industry. Monkeyface and Bleufer mussels are used for this purpose as well, but they are found only in clear flowing streams in southeast Kansas. Another site I explored recently was about a mile downstream from 159th. The site is called “Near a relative’s home”. I was visiting my nieces on their birthday and saw a great opportunity to access the Blue from their backyard. Anyhow, I was more interested in collecting mussels that day than eating cake and ice cream. When I finished my cake, I hurriedly crawled down the banks of the Blue to check for mussels. My young nieces enjoyed the shells I collected from the river. As I recall, I gave them some Mapleleaf shells, which they thought were very cool. Anyway, there was nothing rare or unusual, but it was exciting to find 10 species (Table 2) at this site.

Table 2. Number of mussel species found at Blue River sample sites upstream and downstream from 159th Street site (2009-2013, EPA Region 7)

Figure 3. Mapleleaf (Quadrula quadrula)

Next week stay tuned for the thrilling third and final installation of Mussels in the Blue, where I will discuss the water quality challenges that face the Blue River.

Craig Thompson lives near the mussel-less (except for Asian clams) Brush Creek, a tributary of the Blue River. He is a Life Scientist with the Environmental Assessment and Monitoring Branch (EAMB). Craig joined EPA in 2009 after spending thirteen years with Kansas Department of Health and Environment. He assists EAMB staff with water quality and biological sampling surveys throughout the Region 7 area.

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The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

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For the last four years I have been sampling wadeable streams throughout the metropolitan Kansas City area. I am part of the water monitoring team within the Environmental Assessment and Monitoring Branch (EAMB) at EPA Region 7. I grew up in Mission, Kansas. I was always outdoors exploring the woods behind my parents house and wading the waters of Turkey creek and other creeks in my neighborhood. Now, I am responsible for collecting water and biological samples from some of these same creeks. My particular area of expertise is macroinvertebrate sampling (freshwater mussels and aquatic insects). I am fascinated with the mussel community information that has been collected from several sample sites on the Blue River (Figure 1).

Figure 1

During the 1991-2011 sampling seasons, qualitative mussel surveys were conducted on the Blue River by Kansas Department of Health and Environment (KDHE) and by EPA Region 7. The upper Blue River supports a diverse community of mussels compared to the lower Blue River. The Blue River at 159th Street and Kenneth Road has one of the most diverse mussel communities of any urban stream site in the metropolitan area (Table 1).

There are approximately 45 species of mussels found in Kansas. Kansas Department of Wildlife, Parks and Tourism (KDWPT) lists 6 endangered and 5 threatened species. In addition, they have a category called “species in need of conservation”, or SINC species. There are at least 17 species of mussels found in the Blue River. The site at 159th has one endangered and four SINC mussel species. The Mucket is an endangered mussel found typically in the Marias des Cygnes river basin (several miles south of 159th). This rare mussel is outside its normal range, but it may have occurred in the Blue River (Missouri River Basin) historically. The Creeper, Fatmucket, Wabash pigtoe and Yellow sandshell have interesting names and are SINC species. Creeper (formerly called Squawfoot) is a rare find for this river and only one shell was collected at 159th.

Fatmucket is an unusual name for a mussel. The “fat” part of this mussel’s name probably came from describing the swollen shape of the shell of this species. This characteristic is very common in older individuals and in females. This mussel is doing fair at 159th with a few weathered shells found at other sample sites along the river. Wabash pigtoe and other freshwater mussels are recognized by the shape of their shell. They have either animal hoof or foot characteristics. Names like Fawnsfoot, Round pigtoe, Deertoe, Elktoe and Rabbitsfoot are some of the species in this group. Wabash pigtoe is also doing fair at 159th with some recent and weathered shells found at other sample sites. The Yellow sandshell is a beautiful mussel. The outer layer of the shell (called periostracum) is a distinct yellow and the nacre (the iridescent, inner layer) is silvery-white (Figure 2). The Yellow sandshell is doing well at 159th with some recent shells (unweathered shells) found in 2011. Also, a few recent shells have been collected at other downstream sites.

The other rare mussels identified in the survey may possibly be extirpated (locally extinct) from the Blue River basin. The Pimpleback is common in other streams in the state but is rare in the Blue. It has numerous raised structures on the outer part of its shell called pustules. I have not observed this species for a long time and the last time shells were collected was in 2005. The Pistolgrip is an easy mussel to identify (general shape of a pistolgrip). It is a thick-shelled mussel that is elongate with distinct knobby ridges and pustules. The last time it was discovered at 159th was in 1993. The Plain pocketbook shell is oval and large. It is usually present at 159th and other sites along the Blue but not in high numbers. And, the shell condition is usually weathered or relict. Finally, the Lilliput is a mussel that is hard to find because of its bean-shaped size. Some shells measure around an inch in length and only a few have been collected at 159th.

Next week, I will discuss the relative abundance of species found in the Blue as well as some of the main water quality problems facing mussels in the Blue.

Craig Thompson lives near the mussel-less (except for Asian clams) Brush Creek, a tributary of the Blue River.He is a Life Scientist with the Environmental Assessment and Monitoring Branch (EAMB).Craig joined EPA in 2009 after spending thirteen years with Kansas Department of Health and Environment.He assists EAMB staff with water quality and biological sampling surveys throughout the Region 7 area.

Editor's Note:
The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.

It takes more than the brute strength of legislation to clean up America’s waterways. The complex process of aquatic ecosystem cleanup requires many tools, including one of nature’s most powerful muscles: her freshwater mussels.

That’s what the Partnership for the Delaware Estuary (PDE) – assisted by the Philadelphia Academy of Natural Sciences, and the U.S. Environmental Protection Agency’s (EPA) Scientific Dive Unit – set out to assess during a late summer freshwater mussel survey in a tidal section of the Delaware River near Philadelphia.

Freshwater mussels are bivalves similar to oysters and clams. But, unlike oysters and clams, freshwater mussels live in inland streams, and provide valuable benefits including strengthening streambeds by keeping soils in place and providing food and habitat needed by other animals and plants. As filter-feeders, mussels also clean the water in which they live by sucking water in and trapping solids such as dirt, algae and other pollutants, then releasing the clean filtered water back into the environment.

Being in the tidal area of the Delaware River as a scientific diver was an interesting experience. The water was not clear and flow rates were very high due to tidal fluctuation. In these conditions, I couldn’t help but think, “There’s no way there are mussels down here.” Despite my suspicions, when I reached the river bottom, sure enough, there were mussels everywhere, thriving and filtering the ambient water!

Recording data during the freshwater mussel survey.

Ultimately, the survey, in addition to confirming the existence of an abundant freshwater mussel population in a very urbanized section of the Delaware River and providing valuable scientific data, gave me a newfound appreciation for what I used to only consider a tasty added protein to a pasta dish at a restaurant.*

About the Author:Matt Colip works in the region’s NPDES Enforcement Branch and focuses primarily on enforcing wastewater and stormwater regulations. Originally from Texas, Matt graduated from Franklin & Marshall College in Lancaster, Pa., with an interdisciplinary BA in Public Health and has a MS from Saint Joseph’s University that focused on environmental protection policy and management. In addition to SCUBA diving, Matt is an avid bicyclist and enjoys riding with friends and colleagues.

*EPA is not endorsing the consumption of oysters, clams and mussels in the wild. Please refer to the National Shellfish Sanitation Program guidelines associated with regulating the handling, processing and distribution of mussels prior to consumption.

Editor's Note:
The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.

It takes more than the brute strength of legislation to clean up America’s waterways. The complex process of aquatic ecosystem cleanup requires many tools, including one of nature’s most powerful muscles: her freshwater mussels.

That’s what the Partnership for the Delaware Estuary (PDE) – assisted by the Philadelphia Academy of Natural Sciences, and the U.S. Environmental Protection Agency’s (EPA) Scientific Dive Unit – set out to assess during a late summer freshwater mussel survey in a tidal section of the Delaware River near Philadelphia.

Freshwater mussels are bivalves similar to oysters and clams. But, unlike oysters and clams, freshwater mussels live in inland streams, and provide valuable benefits including strengthening streambeds by keeping soils in place and providing food and habitat needed by other animals and plants. As filter-feeders, mussels also clean the water in which they live by sucking water in and trapping solids such as dirt, algae and other pollutants, then releasing the clean filtered water back into the environment.

Being in the tidal area of the Delaware River as a scientific diver was an interesting experience. The water was not clear and flow rates were very high due to tidal fluctuation. In these conditions, I couldn’t help but think, “There’s no way there are mussels down here.” Despite my suspicions, when I reached the river bottom, sure enough, there were mussels everywhere, thriving and filtering the ambient water!

Recording data during the freshwater mussel survey

Ultimately, the survey, in addition to confirming the existence of an abundant freshwater mussel population in a very urbanized section of the Delaware River and providing valuable scientific data, gave me a newfound appreciation for what I used to only consider a tasty added protein to a pasta dish at a restaurant.

About the Author: Matt Colip works in the region’s NPDES Enforcement Branch and focuses primarily on enforcing wastewater and stormwater regulations. Originally from Texas, Matt graduated from Franklin & Marshall College in Lancaster, Pa., with an interdisciplinary BA in Public Health and has a MS from Saint Joseph’s University that focused on environmental protection policy and management. In addition to SCUBA diving, Matt is an avid bicyclist and enjoys riding with friends and colleagues.

*EPA is not endorsing the consumption of oysters, clams and mussels in the wild. Please refer to the National Shellfish Sanitation Program guidelines associated with regulating the handling, processing and distribution of mussels prior to consumption.

Editor's Note:
The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.